Changes in Plasmodium Falciparum Population Dynamics in Two Populations at Different Time Periods in Ibadan, South-west NigeriaAmodu, O.K.; Olaniyan, S.A. & Omotade, O.O.

Abstract

Changing the malaria epidemiology will affect the genetic diversity of Plasmodium Falciparum. We studied the association
between diversity at the merozoite surface protein 2 loci and the severity of disease in childhood malaria in two populations
and at different time periods in Ibadan, southwest Nigeria. Population A comprised of 164 children (75 acute uncomplicated
malaria (UM), 48 cerebral malaria (CM) and 41 severe malarial anaemia (SMA), while Population B comprised of 225
children (115 UM, 55 CM, 55 SMA). Results showed a high level of genetic diversity and multiplicity of P.falciparum
infections in the two populations. Polyinfections were common in the 2 populations but different (93% for PA and 52% for
PB), the mean multiplicity of infections was different (3.98 per infected person for Population A and 1.80 for Population B.
The presence of polyinfections was significantly lower only in the SMA group in Population A, p=0.007 but significantly
lower in the CM, p=0.003 and SMA groups, p=0.000 in Population B. The presence of FC27 and 3D7 alleles was a significant
predictor of SMA in Population A but not in Population B. The absence of polyinfections (single infections) was found to be a
strong common factor or predictor of severe malaria in the two populations. We conclude that presence of single infections are
associated with the development of severe malaria. In addition, malaria control activities have a great impact on the changing
parasite population dynamics